Year of Award

Document Type

Degree Type

Degree Name

Department or School/College

Committee Chair

Mike Mitchell

Commitee Members

David Naugle, Kerry Foresman

Keywords

feral pigs, habitat selection, home range, sus scrofa, territoriality

Publisher

University of Montana

Abstract

Feral pigs are one of the most successful, widespread, economically and environmentally damaging invasive mammalian species worldwide. I conducted a study of feral pig sounders (female social groups) on Fort Benning, Georgia to test our hypotheses that feral pigs were territorial at the sounder level and that territoriality was a key factor influencing habitat selection of feral pigs. I used Global Positioning System (GPS) location data from 24 individuals representing 18 sounders combined with mark-recapture and camera trap data to evaluate evidence of territorial behavior at the individual and sounder levels by comparing the degree of overlap between home ranges. I categorized the landscape into five land cover types (open grassy areas, upland hardwood forest, pine forest, pine-hardwood forest, and hardwood bottomland forest) based on differences in the food and cover resources they provided feral pigs and used Ivlev's index to evaluate habitat use within sounder home ranges. Sounders had nearly exclusive home ranges and had completely exclusive core areas, suggesting that female feral pigs on Fort Benning were territorial at the sounder level but not at the individual level. Sounders used the majority of forested cover types in proportion to availability and this supports our hypothesis that territorial behavior is a key factor influencing habitat selection by feral pigs on Fort Benning. Furthermore, the need for territory maintenance (patrolling, scent-marking) may mask changes in habitat selection based solely on resource availability. Territorial behavior in feral pigs could influence population density by limiting access to reproductive space. Removal strategies that: 1) match distribution of removal efforts to distribution of territories, 2) remove entire sounders instead of individuals, and 3) focus efforts where high quality food resources strongly influence territorial behaviors may be best for long-term control of feral pigs. Since feral pigs use the majority of forest cover types in proportion to availability, feral pig management actions need to address potential impacts across Fort Benning instead of limiting management actions to hardwood bottoms where pig activity is more apparent.